Controllers are used on a wide variety of devices and systems for controlling various functions in homes and/or buildings and their related grounds. Some controllers have schedule programming that modifies device parameters such as set points as a function of date and/or time. Some such device or system controllers that utilize schedule programming for controlling various functions in homes and/or buildings and their related grounds include, for example, HVAC controllers, water heater controllers, water softener controllers, security system controllers, lawn sprinkler controllers, and lighting system controllers.
HVAC controllers, for example, are often employed to monitor and, if necessary, control various environmental conditions within a home, office, or other enclosed space. Such devices are useful, for example, in regulating any number of environmental conditions within a particular space including, for example, temperature, humidity, venting, air quality, etc. The controller may include a microprocessor that interacts with other components in the HVAC system. For example, in many modern thermostats for use in the home, a controller unit equipped with temperature and humidity sensors may be provided to interact with a heater, blower, flue vent, air compressor, humidifier and/or other components, to control the temperature and humidity levels at various locations within the home or office. A sensor located within the controller unit and/or one or more remote sensors may be employed to sense when the temperature and/or humidity (or other environmental conditions) reaches a certain threshold level, causing the controller unit to send a signal to activate or deactivate one or more component in the system.
The controller may be equipped with an interface that allows the user to monitor and adjust the environmental conditions at one or more locations within the building. With more modern designs, the interface typically includes a liquid crystal display (LCD) panel inset within a housing that contains a microprocessor as well as other components of the controller. In some designs, the interface may permit the user to program the controller to activate on a certain schedule determined by the user. For example, the interface may include a menu routine that permits the user to change the temperature at one or more times during a particular day. Once the settings for that day have been programmed, the user can often repeat the process to change the settings for the remaining days.
Many modern controller have the capability to temporarily override the normal programmed schedule. This may be useful when, for example, a user changes their schedule which deviates from the normal programmed schedule in the controller. For many controllers, a number of steps are often required to establish a one time temporary program override. In some cases, the interface is simply too cumbersome or complex to be conveniently used to program a temporary override. This often results in disabling the normal programmed schedule in favor of manually adjusting the controller. However, when this occurs, the energy saving benefits of the programmable controller are not realized. Accordingly, there is an ongoing need in the art to decrease the time and complexity associated with temporarily modifying a schedule in a programmable controller.